Program Summary/Abstract This T32 renewal application requests funds over five years to support six (6) predoctoral traineeships in population research at the Center for Demography and Ecology (CDE) at the University of Wisconsin-Madison. Since 1962, CDE has offered a world-class training program in population science (with nearly continuous NICHD T32 funding since 1975). Our graduates are among the leaders in population research today, serving in a range of academic, government and applied research settings. Guided by the NICHD mission ?to ensure the health, productivity, independence, and well-being of all people,? CDE research is organized around five major areas: 1) Fertility, families & households; 2) the Demography of Inequality; 3) Health & mortality; 4) Biodemography; and 5) Environmental and spatial demography. Our training objectives?and associated research activities?fall squarely under the Population Dynamics Branch which ?supports research and research training in demography, reproductive health, and population health.? The primary goals of the CDE training program in demography are: (1) to foster an interdisciplinary community of junior scholars in population research; (2) to build expertise in demographic theory, methods, and analysis; and (3) to cultivate students' professional skills, including the organization, execution, presentation, publication, and critique of research. Within the CDE training program, the process of developing this expertise involves four essential components: (1) formal training via coursework in students' home departments and interdisciplinary coursework in other departments; (2) exposure to cutting-edge research of scholars in the broader community of population studies, primarily through the weekly Demography Seminar (`DemSem'); (3) participation and collaboration in substantive research projects of CDE training faculty through an apprenticeship model; and (4) professional socialization and integration into the field of population studies, especially via the weekly Demography Training Seminar. Predoctoral T32 trainees are typically appointed in the second or third year in their PhD program, having shown clear academic promise and a strong commitment to pursuing a population research-related career; most students come from Sociology, Economics and Population Health (although we are increasingly recruiting from a broader range of disciplines), and they typically receive T32 funding for two to three years. We are requesting 6 predoctoral training slots (1 more than our current allocation) because our program has continued to grow in size, scope and quality. Our training efforts have expanded to focus on interdisciplinary research areas at the forefront of social science (especially biodemography and spatial/environmental demography), and we have been very successful at recruiting even larger numbers of highly-competitive students into our broader training program. For the 2016-17 academic year, 8 top-notch, first-year students in Sociology and several enrolled students in Economics and Population Health will join our existing group of 26 demography trainees. Having a critical mass of T32 traineeships ensures that we can continue to support our most outstanding students in what we believe is one of the best available environments for predoctoral training in population research.